1. Field of the Invention
The present invention relates to an image forming apparatus such as an electrophotographic recording apparatus and a copying machine, and to a toner cartridge that is removably attached to an image forming apparatus.
2. Description of the Related Art
One conventional electrophotographic recording apparatus such as an electrophotographic color recording apparatus incorporates a plurality of image-forming apparatuses for toner images of different colors, aligned in a direction in which a print medium travels. Each image-forming apparatus includes a photoconductive drum on which an electrostatic latent image is formed, and a developing unit by which the electrostatic latent image is developed with toner into a toner image.
The developing unit includes a developing roller in pressure contact with the photoconductive drum and a toner-supplying roller which in turn is in contact with the developing roller. A toner cartridge holds toner therein and is attached to the developing unit. The toner cartridge has an opening through which the toner is discharged into the developing unit.
The developing unit has a toner agitator that is located immediately below the opening of the toner cartridge and agitates the toner to prevent toner clumping. The image-forming apparatus has a toner detector that detects an amount of remaining toner.
The aforementioned conventional toner cartridge discharges the toner therein over the toner agitator on the image-forming apparatus side. Therefore, the toner cartridge has to be mounted at a specific location relative to the image-forming apparatus. This is detrimental to miniaturization of the image-forming apparatus. In particular, the dimension in the direction of travel of the print medium is difficult to be made smaller.
An object of the present invention is to provide a toner cartridge having a remaining toner detecting mechanism that detects an amount of toner remaining in a toner chamber.
An object of the present invention is to provide a toner cartridge that can detect an amount of toner remaining in a toner chamber and an image forming apparatus that can indicates to a user when the toner chamber in the chamber is nearing exhaustion.
An object of the present invention is to provide a toner cartridge and an image-forming apparatus that can be miniaturized so that the dimension in the direction of travel of the print medium can be smaller.
A toner cartridge is attached to an image forming apparatus. The toner cartridge has an opening through which toner is discharged into a developing unit of the image forming apparatus. The toner cartridge includes:
a toner chamber that holds the toner therein; and
a toner agitating mechanism that is driven to agitate the toner in the toner chamber, the toner agitating mechanism having an agitating member that agitates the toner in the toner chamber, and a coupling member that is coupled to the agitating member and displaced in accordance with a motion of the agitating member.
The coupling member has a first end and a second end, the first end being connected to a remaining-toner detecting element; and
The agitating member has an agitating element that agitates the toner in the toner chamber and a transmitting element coupled to the second end of the coupling member, the transmitting element operating together with the agitating member to transmit the motion of the agitating member to the second end of the coupling member.
The toner agitating mechanism includes:
a crank shaft that includes a first crank pin that agitates the toner and a second crank pin that is formed in the crank shaft, the crank shaft being rotatably supported in the toner chamber;
wherein the coupling member has a first end rotatably coupled to the second crank pin and a second end slidably inserted in a guide path provided above the toner chamber, the second end having a remaining-toner detecting element provided thereto.
The remaining-toner detecting element may be a magnetic material.
The remaining-toner detecting element may be a permanent magnet.
A toner cartridge and an image forming apparatus are combined such that the toner cartridge is detachably attached to the image forming apparatus. The toner cartridge has an opening through which toner is discharged into a developing unit of the image forming apparatus. The toner cartridge includes a first mechanism having an agitating member that is driven to agitate the toner in the toner chamber. The first mechanism has an agitating member that is driven to agitate the toner in a toner chamber. The first mechanism included remaining toner detecting mechanism that detects an amount of toner remaining in the toner chamber. The image forming apparatus include a second mechanism that detects an operation of the remaining-toner detecting mechanism.
The remaining toner detecting mechanism includes:
a transmitting element formed in the first mechanism, the transmitting element operating together with the first mechanism; and
a coupling member having a first end coupled to the transmitting element and a second end to which a remaining-toner detecting element is provided.
The second mechanism includes:
a sensor lever and a photosensor, the sensor lever operating in response to a movement of the coupling member to cause the photosensor to selectively become ON and OFF.
The sensor lever has one end thereof to which a magnetic flux-sensitive element is attached, the magnetic flux sensitive element opposing the remaining-toner detecting element at the second end of the rod.
The sensor lever has one end thereof to which a magnet is attached, the magnet opposing the remaining-toner detecting element at the second end of the coupling member.
The sensor lever includes a first lever and a second lever coupled to the first lever such that the second lever is pivotal relative to the first lever in an upward direction;
wherein the image forming apparatus is vertically movable between an up position and a down position;
wherein when the image forming apparatus is at the down position, the first lever and the second lever cooperate to detect the remaining-toner in the toner chamber; and
wherein when the image forming apparatus is at the up position, the image forming apparatus pushes the second lever in the upward direction so that the second lever pivots relative to the first lever not to detect the remaining-toner in the toner chamber.
The second mechanism includes a Hall effect element.
The Hall effect element is resiliently urged against a wall that separates the Hall effect element from one end of the remaining toner detecting mechanism. The toner cartridge is vertically movable between an up position and a down position when the image forming apparatus moves. When the image forming apparatus moves to the down position, the Hall effect element is resiliently extended in a downward direction to detect the remaining-toner in the toner chamber. When the image forming apparatus moves to the up position, the Hall effect element is resiliently retracted in the upward direction not to detect the remaining-toner in the toner chamber.
The first mechanism includes:
a crank shaft that includes a first crank pin that agitates the toner, the crank shaft being rotatably supported in the toner chamber;
wherein the remaining toner detecting mechanism comprises:
a second crank pin formed in the crank shaft; and
a coupling member having a first end rotatably coupled to the second crank pin and a second end slidably inserted in a guide path provided above the toner chamber, the second end having a remaining-toner detecting element provided thereto.
The remaining-toner detecting element may be a magnetic flux-sensitive element.
The remaining-toner detecting element may be a permanent magnet.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.